NonStop S-Series Server Description Manual (G06.24+)

Introduction

HP NonStop S-Series Server Description Manual—520331-003

1-32

Maximum I/O for Four Processor Enclosures

In tetrahedral topologies, two SEBs for each fabric are required in order to include the

I/O enclosures. The arrangement is as shown in Figure 1-17. In this case, the four SEB

routers that implement the tetrahedron are not available for connection to I/O

enclosures. However, the added four SEBs each provide for connection of five I/O

enclosures. With all of the available router ports connected, 20 I/O enclosures can

therefore be supported.

The I/O enclosures are designated I/1 through I/20, just as the processor enclosures

are designated P/1 through P/4.

All of the I/O enclosures can support up to 18 ServerNet addressable controllers

(SACs) as shown in Figure 1-10 on page 1-19: five on each multifunction I/O board

(MFIOB) and one or two on each ServerNet adapter.

The arrows in the processor enclosures designate router connections to the

processors.

For simplicity, the Y fabric connections are not shown.